随便搜搜就能知道的，简单的说就是没拿过购房津贴

Check if you are a first-timer applicant
You will be considered a first-timer applicant if you have not received any housing subsidy from HDB. This means that you must not:

Be the owner of a flat bought from HDB
Have sold a flat bought from HDB
Have bought an Executive Condominium (EC), Design, Build and Sell Scheme (DBSS) flat or an HDB resale flat with CPF Housing Grant, or taken over ownership of such a flat or EC
Have transferred the ownership of a flat bought from HDB, or an HDB resale flat bought with a CPF Housing Grant
Have ever taken other forms of housing subsidy, such as Selective En bloc Redevelopment Scheme benefits or HUDC estate privatisation